It is known from the prior art to equip mobile devices for data communication with radio units for different radio networks with different radio standards, as a result of which these devices can support different radio standards.
Different radio standards have different quality parameters, such as for example range, data rates, etc. Generally, radio standards which guarantee a large range have a low bandwidth and thus a low transmission rate or data rate, wherein radio standards with a high bandwidth and thus with a high transmission rate or data rate have a smaller range and thus coverage compared to narrow band radio standards.
Broadband in this case represents transmissions with higher data rates, narrow band represents transmissions with somewhat lower data rates. This colloquial definition is based on the observation that one also tends to consume more space in the spectrum when transmitting more data in the same unit of time. A narrow band radio network (i.e. a radio network based on a narrow band radio standard) in the sense of the invention has a larger range and a lower data rate than a broadband radio network.
A plurality of base stations or relatively small cells are necessary in order to ensure good coverage in the case of radio standards with high bandwidth. Due to the low range of broadband systems, it is ensured that less interference loads the transmission path, as a result of which transmission errors are largely prevented.
In the event that at a location, a wireless connection between a mobile device and radio networks is possible via different radio standards, according to the prior art, hard switching between the different radio standards takes place as a function of requests with respect to the coverage, the transmission costs, the signal quality, etc. Here, the existing connection via one radio standard is deactivated, whilst another connection via another radio standard is activated.
This may disadvantageously lead to no wireless connection being present for a certain time during the switching from one radio standard to another radio standard, so that dead times result, as the mobile device first has to perform a log in and/or authentication in the case of the radio network to be used.
Further, it is known in the case of the availability of a plurality of radio networks with different radio standards to only deactivate an existing connection via one radio standard if another connection via another radio standard is established. As, however, the time of the breaking of the existing connection cannot be established exactly, this procedure can likewise result in dead times.
Furthermore, due to the short range of broadband radio standards, it is necessary to frequently change the base stations of a broadband radio standard, for example of a WLAN system, which disadvantageously results in an overlapping of the frequency ranges of the base stations one the one hand, which can lead to interferences, and results in dead times on the other hand, as the mobile device must first seek a new base station and carry out a log in and/or authentication if the contact to the previous base station is already interrupted.